汽車理論課后題matlab程序

1、精品1.3n=600:1:4000; r=0.367; i0=5.83; eff=0.85; f=0.013;m=3880; g=9.8; G=m*g; CdA=2.77; a=1.947; hg=0.9; L=3.2;Iw1=1.798; Iw2=3.598; Iw=Iw1+Iw2; If=0.218;Ttq=-19.313+295.27*n/1000-165.44*(n/1000).2+40.874*(n/1000).3-3.8445*(n/1000).4;% 驅(qū)動力行駛阻力平衡圖for ig=5.56,2.769,1.644,1.00,0.793Ua=0.377*r*n/ig/i0;Ft

2、=Ttq*ig*i0*eff/r;plot(Ua,Ft);hold on;endFf=G*f;ua=0:0.1:max(Ua);Fw=CdA*ua.2/21.15;plot(ua,(Ff+Fw); title('驅(qū)動力 -行駛阻力平衡圖'); xlabel('Ua/(km/h)');ylabel('Ft/N');gtext('Ft1'),gtext('Ft2'),gtext('Ft3'),gtext('Ft4'),gtext('Ft5'),gtext('Ff+

3、Fw')x,y=ginput(1); disp('汽車的最高車速');disp(x);disp('km/h');% 最大爬坡度及最大爬坡度時的附著率Ua=0.377*r*n/5.56/i0;Ft=Ttq*5.56*i0*eff/r;-可編輯 -精品Fw=CdA*Ua.2/21.15;i=tan(asin(Ft-(Ff+Fw)/G);disp(' 汽車的最大爬坡度');disp(max(i);C=max(i)/(a/L+hg/L*max(i);disp(' 克服最大爬坡度時的附著率');disp(C);% 加速度倒數(shù)曲線fi

4、gure;for ig=5.56,2.769,1.644,1.00,0.793Ua=0.377*r*n/ig/i0;q=1+Iw/(m*r2)+If*ig2*i02*eff/(m*r2);Ft=Ttq*ig*i0*eff/r;Fw=CdA*Ua.2/21.15;as=(Ft-(Ff+Fw)/q/m;plot(Ua,1./as);hold on;endaxis(0 98 0 10);title(' 行駛加速度倒數(shù)曲線');xlabel('Ua/(km/h)');ylabel('1/a');gtext('1/a1'),gtext(&#

5、39;1/a2'),gtext('1/a3'),gtext('1/a4'),gtext('1/a5');% 加速時間曲線u(1)=0.377*r*600/i0/2.769;dt=0.01;w=1;t(1)=0;ig=2.769;while(u(w)<99.08)-可編輯 -精品n(w)=u(w)*ig*i0/0.377/r;Ttq(w)=-19.313+295.27*n(w)/1000-165.44*(n(w)/1000)2+40.874*(n(w)/1000)3-3.8445*(n(w)/1000)4;Ft(w)=Ttq(w)*i

6、g*i0*eff/r;Ff=G*f;Fw(w)=CdA*u(w)2/21.15;q=1+Iw/(m*r2)+If*ig2*i02*eff/(m*r2);a(w)=3.6*(Ft(w)-(Ff+Fw(w)/q/m;u(w+1)=u(w)+a(w)*dt;if(u(w+1)>=0.377*4000*r/2.769/i0)ig=1.644;endif(u(w+1)>=0.377*4000*r/1.644/i0)ig=1.00;endif(u(w+1)>=0.377*4000*r/1.00/i0)ig=0.793;endt(w+1)=(w+1)*dt;w=w+1;end-可編輯 -精

7、品figure;plot(t,u);axis(0 60 0 100);title('2擋原地起步加速時間曲線');xlabel('時間t/s'),ylabel('車速 u/(km/h)');x1,y1=ginput(1);disp('加速到 70km/h的時間 ');disp(x1);驅(qū)動力-行駛阻力平衡圖14000Ft112000100008000N/tFt2F60004000Ft32000Ft4Ff+FwFt50Umax=99.07204060801001200Ua/(km/h)行駛加速度倒數(shù)曲線1098761/a5a/514

8、1/a4321/a311/a21/a101020304050607080900Ua/(km/h)-可編輯 -精品2擋原地起步加速時間曲線100908070)h60/mk(/50u速車 4030201000102025.8830405060時 間 t/s1.8Iw1=2.25; Iw2=2.25; Iw=Iw1+Iw2; If=0.25; m=1600;g=9.8;G=m*g;Ttqmax=140; i1=3.85; i0=4.08; eff=0.9; r=0.3; hg=0.63; b=1.25; L=2.7;q=1+Iw/(m*r2)+If*i12*i02*eff/(m*r2);Ft=Ttq

9、max*i1*i0*eff/r;a=Ft/q/m;q=a/g;C1=q/(b/L-hg/L*q);if(C1>0.6)disp(' 發(fā)動機轉(zhuǎn)矩不能充分發(fā)揮');elsedisp(' 發(fā)動機轉(zhuǎn)矩能夠充分發(fā)揮');end-可編輯 -精品b=(q/0.6+hg/L*q)*L;disp(' 調(diào)整后的b 值 ');disp(b);disp(' 調(diào)整后的前軸負荷率'),disp(b/L);1.9Iw=3.6; If=0.22; m=2152; g=9.8; r=0.367; eff=0.9; i4=1; i0=4.55;amax=0.7

10、5; Ua=50/3.6; CdA=1.5;q=1+Iw/(m*r2);f=q*0.59/3.6/g;disp(' 汽車在該路面上的滾動阻力系數(shù)');disp(f);q=1+Iw/(m*r2)+If*i42*i02*eff/(m*r2);D4max=f+q*amax/g;disp(' 最大動力因數(shù) ');disp(D4max);Fw=CdA*Ua2/21.15;D1max=(D4max*G+Fw)*i1/i4/G;imax=tan(asin(D1max-f*sqrt(1-D1max2+f2)/(1+f2);disp(' 最大爬坡度 '),disp

11、(imax);2.7n=600:1:4000; r=0.367; i0=5.83; eff=0.85; f=0.013;CdA=2.77;m=3880; g=9.8;G=m*g;Ttq=-19.313+295.27*n/1000-165.44*(n/1000).2+40.874*(n/1000).3-3.8445*(n/1000).4;for ig=5.56,2.769,1.644,1.00,0.793-可編輯 -精品Ua=0.377*r*n/ig/i0;Pe=Ttq.*n/9550;plot(Ua,Pe);hold on;endUa=0:0.1:max(Ua);Pf=G*f*Ua/3600;

12、Pw=CdA*Ua.3/76140;plot(Ua,(Pf+Pw)/eff);title(' 汽車的功率平衡圖'),xlabel('Ua/(km/h)'),ylabel('P/kw');% 等速百公里燃油消耗n1=815,1207,1614,2012,2603,3006,3403,3804;b0=1326.8,1354.7,1284.4,1122.9,1141.0,1051.2,1233.9,1129.7;b1=-416.46,-303.98,-189.75,-121.59,-98.893,-73.714,-84.478,-45.291 ;b2=

13、72.379,36.657,14.524,7.0035,4.4763,2.8593,2.9788,0.71113;b3=-5.8629,-2.0553,-0.51184,-0.18517,-0.091077,-0.05138,-0.047449,-0.00075215;b4=0.17768,0.043072,0.0068164,0.0018555,0.00068906,0.00035032,0.00028230,-0.000038568;B0=spline(n1,b0,n); B1=spline(n1,b1,n); B2=spline(n1,b2,n); B3=spline(n1,b3,n);

14、B4=spline(n1,b4,n);deng=7;-可編輯 -精品figure;for ig=1.00,0.793Ua=0.377*r*n/ig/i0;Pf=G*f*Ua/3600;Pw=CdA*Ua.3/76140;P=(Pf+Pw)/eff;b=B0+B1.*P+B2.*P.2+B3.*P.3+B4.*P.4;Q=P .*b./(1.02*Ua*deng);plot(Ua,Q);hold on;endaxis(0 100 12 28);title(' 最高擋與次高擋等速百公里油耗曲線'),xlabel('Ua/(km/h)'),ylabel('百公

15、里油耗Qs/(L/100km)');-可編輯 -精品汽車的功率平衡圖10090(Pf+Pw)/eff8070wk/P)mk001/L(/sQ耗油里公百601234550403020100020406080100120Ua/(km/h)最高擋與次高擋等速百公里油耗曲線2826242220五 擋1816四 擋1412020406080100Ua/(km/h)4.3beta=0.38; L=3.95; a1=2.1; b1=L-a1; hg1=0.845;a2=2.95; b2=L-a2; hg2=1.17;g=9.8;z=0:0.01:1;-可編輯 -精品faif1=beta*z./(1/

16、L*(b1+z*hg1);fair1=(1-beta)*z./(1/L*(a1-z*hg1);faif2=beta*z./(1/L*(b2+z*hg2);fair2=(1-beta)*z./(1/L*(a2-z*hg2);plot(z,faif1,'r',z,fair1,'g',z,faif2,'b',z,fair2,'k');fai=0:0.01:1;Ef1=(b1/L)./(beta-fai*hg1/L);Er1=(a1/L)./(1-beta)+fai*hg1/L);Ef2=(b2/L)./(beta-fai*hg2/L);

17、Er2=(a2/L)./(1-beta)+fai*hg2/L);figure;plot(fai,Ef1,'r',fai,Er1,'g',fai,Ef2,'b',fai,Er2,'k');axis(0 1 0 1);fai=0.8;Er1=(a1/L)/(1-beta)+fai*hg1/L);Er2=(a2/L)/(1-beta)+fai*hg2/L);abmax1=fai*Er1*g;abmax2=fai*Er2*g;t21=0.02; t22=0.2; u0=30;s1=1/3.6*(t21+t22/2)*u0+u02/25.9

18、2/abmax1;s2=1/3.6*(t21+t22/2)*u0+u02/25.92/abmax2;disp(' 空載時的制動距離'),disp(s1);-可編輯 -精品disp(' 滿載時的制動距離'),disp(s2);% 前部管路損壞時制動距離z1=a1*fai/(L+fai*hg1); z2=a2*fai/(L+fai*hg2);abmax1=z1*g; abmax2=z2*g;s1=1/3.6*(t21+t22/2)*u0+u02/25.92/abmax1;s2=1/3.6*(t21+t22/2)*u0+u02/25.92/abmax2;disp(&#

19、39; 前部管路損壞時空載制動距離');disp(s1);disp(' 前部管路損壞時滿載制動距離');disp(s2);% 后部管路損壞時的制動距離z1=b1*fai/(L-fai*hg1);z2=b2*fai/(L-fai*hg2);abmax1=z1*g; abmax2=z2*g;s1=1/3.6*(t21+t22/2)*u0+u02/25.92/abmax1;s2=1/3.6*(t21+t22/2)*u0+u02/25.92/abmax2;disp(' 后部管路損壞時空載制動距離');disp(s1);disp(' 后部管路損壞時滿載制動

20、距離');disp(s2);4.5hg=0.63; b=1.25; L=2.7; beta=0.65; fai=0.7; g=9.8;fai0=(L*beta-b)/hg;if(fai<fai0)disp(' 前輪先抱死 ,制動效率為 '); E=(b/L)/(beta-fai*hg/L);elsedisp(' 后輪先抱死 ,制動效率為 '); E=(a/L)/(1-beta)+fai*hg/L);-可編輯 -精品enddisp(' 最大制動減速度'),disp(E*fai*g);disp('a)、 b) 、c) 的雙回路制動系統(tǒng)制動系增益都為G');disp('1回路失效時， a) 、 b) 、 c)的制動系增益分別為0.35,0.5,0.5');disp(